Comparison of methods to assess energy expenditure and physical activity in people with spinal cord injury

Objective: To compare different methods of assessing energy expenditure (EE) and physical activity (PA) in people with spinal cord injury (SCI) under community-dwelling conditions. Methods: A reference standard encompassing the doubly labelled water (DLW) technique, heart rate monitoring (FLEX-HR), a multi-sensor armband (SenseWear Armband (SWA)), and two PA recall questionnaires were employed in 14 people with SCI to estimate EE and leisure-time PA. Results: Mean total daily energy expenditure (TDEE) assessed by DLW, FLEX-HR, and SWA were 9817 +/- 2491 kJ/day, 8498 +/- 1516 kJ/day, and 11414 +/- 3242 kJ/day, respectively. Physical activity energy expenditure (PAEE) quantified by DLW was 2841 +/- 1626 kJ/day, 2935 +/- 1732 kJ/day estimated from FLEX-HR, and 2773 +/- 2966 kJ/day derived from SWA. After converting the PA recall questionnaire data to EE in kJ/day, PAEE for the Physical Activity Recall Assessment for People with Spinal Cord Injury (PARA-SCI) was 2339 +/- 1171 kJ/day and for Physical Activity Scale for Individuals with Physical Disabilities (PASIPD) 749 +/- 1026 kJ/day. DLW-quantified PAEE was moderately associated with PARA-SCI (R-2 = 0.62, P < 0.05), but not with the other estimates of PAEE (R2 ranged between 0.13 and 0.30, P > 0.05). Conclusion: Our findings revealed that the PARA-SCI recall questionnaire was the best estimate of PAEE compared to the reference standard DLW approach. Although the between-method variability for SWA, FLEX-HR, and PASIPD-derived PAEE was small, there was a weak association between these methods and the criterion DLW technique. The best estimate of DLW-quantified TDEE was by FLEX-HR. SWA significantly overestimated TDEE in this population.